66942609 has 8 divisors (see below), whose sum is σ = 92136192. Its totient is φ = 43188720.

The previous prime is 66942607. The next prime is 66942611. The reversal of 66942609 is 90624966.

It is an interprime number because it is at equal distance from previous prime (66942607) and next prime (66942611).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66942609 - 2¹ = 66942607 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66942607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 359814 + ... + 359999.

It is an arithmetic number, because the mean of its divisors is an integer number (11517024).

Almost surely, 2^66942609 is an apocalyptic number.

It is an amenable number.

66942609 is a deficient number, since it is larger than the sum of its proper divisors (25193583).

66942609 is a wasteful number, since it uses less digits than its factorization.

66942609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719847.

The product of its (nonzero) digits is 139968, while the sum is 42.

The square root of 66942609 is about 8181.8463075274. The cubic root of 66942609 is about 406.0388086047.

The spelling of 66942609 in words is "sixty-six million, nine hundred forty-two thousand, six hundred nine".